Why CT secondary winding should never be open-circuited

The CT’s secondary winding should never be open-circuited! Since, Open-circuiting a CT’s secondary winding may result in a dangerous amount of voltage developing between the secondary terminals because the CT will attempt todrive a substantial current through a very high resistance. This is why you will never see fuses in the secondary circuit of a … Read more

Why PT Secondary Winding should never be Short-Circuited

A PT’s secondary winding should never be short-circuited, since Short-circuiting a PT’s secondary winding may result in a dangerous amount of current developing in the circuit because the PT will attempt to maintain a substantial voltage across a very low resistance. Also see: Why CT secondary winding should never be open-circuited While the recommendation to … Read more

What is meaning of Letters A, B, C, and F on Potentiometers

Letters A, B, C, and F on Potentiometers indicate relationship between slider position and resistance of potentiometer. The relationship between slider position and resistance is also sometimes known as the “taper” or “law”. This relationship can be controlled during manufacture by changing the composition or thickness of the resistance coating along the resistance element. Potentiometers … Read more

Why silver is not used in overhead transmission lines – 5 Reasons

Electrical Engineering XYZ Question on Why silver is not used in overhead transmission lines. Answer: Silver is an excellent conductor of electricity, even better than copper. However, there are several reasons and certain limitations because of which silver is not widely used for this purpose. While cost is the major and primary reason for that, … Read more

Why Insulators have negative temperature coefficient of resistance

The temperature coefficient of resistance (TCR) is a measure of how much an electrical resistance of material changes with temperature. The temperature coefficient can be positive, negative, or zero. A negative temperature coefficient of resistance (NTC) means that the resistance of the material decreases as the temperature increases. In other words, as the temperature rises, … Read more

How many volts are Dangerous Volts for Humans – Voltage Threshold Value

One of very common Electrical Engineering safety related questions in about volts. In this article Electrical Engineering XYZ shares how many volts are dangerous volts for humans. In industry, 30 volts is generally considered to be a conservative threshold value for dangerous voltage. The cautious person should regard any voltage above 30 volts as threatening, … Read more